What is over temperature warning system?

An over temperature warning system consists of a temperature sensor combined with an warning system. The temperature sensor will be continuously monitoring the temperature. The sensor can be programmed to check the temperature at different intervals.

The second element of the system is an alert system. The alert can be different types. In case the temperature goes above or below the programmed levels, the following warning can be generated:

Phone call alerts to operators (calls can be made for upto 10 number)

SMS alerts to same operators

Email alerts to any number of emails addresses

Local siren / beacon lamps

What should be the temperature sampling interval?

Depending on the critical nature of the area being monitored, the interval can be programmed. This interval is known as sampling interval.

For a cold room of 2-8°C, the sampling interval is set between 1 and 3 minutes. The reason is that this is a narrow range of temperature. Also you may not want the temperature to go beyond the limits even for couple of minutes. Hence the sampling interval is kept at low levels. The recommended sampling interval is not more than 3 minutes.

Whereas for a warehouse of temperature range between 15-25°C, the sampling interval can be set at 10 or 15 °C.

What should be the warning levels?

The higher and lower alarms have to be programmed in the system. Eg. If you want the temperature of the cold room to be between 2 and 8°C, you can set the alerts as below:

Higher warning should be activated if the temperature goes above 7.5°C for 5 minutes

Lower warning should be activated if the temperature goes below 2.5°C for 5 minutes

You may notice that the higher alert level is kept 0.5°C below the permitted level so that if a warning is generated, someone can attend the problem before it crosses 8°C. Also you may notice that there is a time delay of 5 minutes programmed. The reason is to avoid false alarms, probably caused by temporary conditions such as a door opening. When a door is opened, the temperature may go above 7.5°C briefly. You may not want to have warnings at such short excursions.

What are the other alerts possible in this system?

You may decide to combine following alerts in the same system

Alerts for over temperature or under temperature

Alerts in case of power failure

Alerts for excursions of humidity

Alerts for door opening / closing

Alerts for water leakage

Alerts for Smoke detection

What features you should consider in a temperature warning alert system?

Most importantly, the alerts should be generated even in case of a power failure. So the system should work on battery.

The alerts should be generated even in case of a internet failure or failure of your server

The data should be accessible to be viewed through internet even from outside. In this case when you receive a phone call alert you should be able to check continuous data through internet.